Mechanism for decorticating fibers obtained from the leaves of sisal and like plants



April 1940- J. McCRAE 2 2,197,242 MECHANISM FOR DECORTICATING FIBERSOBTAINED FROM THE LEAVES OF SISAL AND LIKE PLANTS Filed July 26, 1957 3Sheets-Sheet l A770 IVE/V5 April 16, 1940.

J. M CRAE 2,197,242 MECHANISM FOR DECORTICATING FIBERS OBTAINED FROM THELEAVES OF SISAL AND LIKE PLANTS Filed July 26, 1937 20 I/VVF/VTUA Jamesmccrwr. 8)

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ATTORNEYS 3 Sheets-Sheet 2 April 16, 1940. CRAE 2,197,242

.. J. Mc MECHANISM FOR DECORTICATING FIBERS OBTAINED FROM THE LEAVES OFSISAL AND LIKE PLANTS Filed July 26, 1937 3 -Sheet 3 Fig. 7

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1 llllllllllllllllllllj Tamas 40 MQETQQ Patented Apr. 16, 1940 M UNITEDSTATES'P'ATENT OFFlCE MECHANISM FOR DECORTIGATING FIBERS OBTAINED FROMTHE LEAVES OF SISAL AND LIKE PLANTS James McGrae, Longonot Estate,Naivasha, Kenya Colony, East Africa.

Application July 26, .1937, Serial No. 155,683. Renewed March 8, 1940.In Great Britain August 6, 1936 3 Claims. (01. 19-15) This inventionrelates to mechanism for Fig. '7 shows a modification of the blade anddecorticating fibers obtained from the leaves of the method of mountingsame as compared with sisal and other plants, and my present inventionFig. 5. consists in devices and mechanism for further Fig, 8 also Showsa modification of said blade .5 treating the fibers after they have beenprepared and the method of mounting same upon the v and acted upon bythe mechanism described in lattice bar.

the specification of my further concurrent appli- Fig. 9 is a drawing indetail showing a method cation for Letters Patent Ser. No. 155,682,filed of securing the blade carrying member mounted simultaneouslyherewith, or fibers similarly upon the lattice bar referred to.

10 treated by any other process than that as ex- Fig. 10 shows amodification in the shape of 1p plained by my said specification. theoperating blades shown by Figs. ,5, 6, 7 and 8,

My said invention comprises the employment said modification comprisingthe said formation of machinery or mechanism for carrying out the toenable said blade to act as is hereinafter fully treatment whereby theforce acting upon the explained.

threads of fibers lays such stress or tensional Fig. 11 is a planshowing how the threads, as 15 strain thereon that the separate fibersin their they are separated and treated by the blades, are naturalbundled state are forced or burst asunder caused 'to be cleaned,strained and stressed as or caused to'separate in increasing degree fromdesired. each other.(as well as all the other substances Fig. 12 is aplan drawn to a reduced scale accompanying same), the said process ofseparashowing somewhat how the series of blades may 2 tion being carriedout to any desired degree be varied throughout the length ofeach of theappropriate to the preparation of the fibers for lattice bars upon whichsaid blades are mounted. any of the particular purposes for which theyFig. 13 is a diagrammatical plan and Fig. 14 a may subsequently be used.diagrammatical elevation (seen in the direction, of

In carrying my invention into effect I make arrow 40, Fig. 13) of themain operating parts of 5 use of the mechanism and devices herein-aftera machine (drawn to areduced scale) to show the d c be y reference 110 tcco p nying relative positions of the said operating parts. sheets ofdrawings, in which: To attain the object of my invention I make l i a Seon e d e t on ow ng he use of feed mechanism comprising two pairs ofoperating belt devices for feeding the prepared travelling chains 2, 2aand 2b, 20, one chain of '30 leaves to two pairs of lattice belt devicescarrying each pair 2 or 2b being superposed to travel in a ades forsubjecting S leaves to their Defies path over the path in which theother chain of trati e, m v d cleaning p a s on the the pair 2a or 20travels in order that the crushed fibers d ved om d leaVeS- leaves w(Fig. 3), with their cutieles or coverings 2 s a sectional p a of a p nof t and other matter, may be fed to the chains 3, 35

devices shown by Fig. 3a and 3b, 30, as is hereinafter explained.

Fls. 3 1 a slmi r vi w o Fla 1 bu shows on The formation andconstruction of said pair of feeding b devices n n t n wit travellingchains 2, 2a and 2b, were such that One P Of lhttlce belt Carrylng bladedevlces, their surfaces 3: (see Fig. 3) will contact with 40 the Samebeing dram} an enlarged Scale in each other, and by being covered withindia ruborder more clearly to illustrate the construction t each chaincarrying its respective rubber of my improved parts.

g 4 shows the chain pp g wheel p I covering formed as shown at a: (Fig.3) is enabled which the belt-gripping-devices shown by Fig. 3 i to actas Jaw or gripping member that W111 are mounted said belt grippingdevices being firmly gripthe sheets or bundles of fibers fed mountedupon the chains arranged according to to F the gnppmg acnons bemgSecured P 45 my invention. spring actuated members that force one chalnFig. 5 is a side elevation of one of my improved i the other Whlle Wherenecessary piercing, removing, Smoothing and scraping frictionbowls .9may be mounted upon. the chains blades mounted upon one of the latticebars to travelsoverthe guiding s4 i0h support 50 forming the latticedriving belt shown by Figs. them- 1 2 and v v The india rubber beltsurfaces as are endless so Fig. 6 is a'side elevationof the membersshown that they may ak v a d circulate y th by Fig. 5 as seen lookingfrom right to left of said rotary actions of their operating sprocketwheels figure. -5 which are mounted at the extremities of the 555 pathsthrough which the belts 2, 2a, 2b and 20 travel.

Adjacent the vertical planes in which the gripping chains, 2, 2a, 2b and2c operate, and parallel therewith, are mounted two shafts I0, Illa andlllb, lllc respectively, by which arrangement the sprocket wheelsmounted upon the shafts H], 10a and I01), I00 revolve in planes at rightangles to the planes in which the gripper chains 2, 2a. and 2b, 20travel.

Upon these-shafts It to I00 are mounted the desired number of sprocketwheels (all of which are referred to as I l) so that the lattice beltsor chains 3, 3a and 3b, 3c may take over these sprocket wheels II andextend to take also over sprocket wheels l2 mounted upon shafts parallelthereto. These lattice belts 3 to' 30 are provided with cross bars orstaves I l, Ma and Mb, I lc, those staves at i l and Mb being thuscaused to travel through paths vertically above the paths in which thestaves Ma. and Me operate.

In appropriate base members l5 which are fixed upon the staves Ma and Meare mounted blades it which have base parts 16a of appropriateconstruction or formation to suit their fitting within the hollowretaining member I5, from which it will be observed that themodification in said base part Mia, from fitting one fixing member oranother fixing member, varies from the rectangular shape shown by Fig. 5to those shown by Figs. '7 and 8, in each case the base member [5 beingsecured against rotation upon the stave or bar Ma by the fixing memberl5w as circumstances necessitate.

Upon the staves I l and Mb which travel in paths above the paths inwhich the staves Ma and We travel cross bars of an appropriate shape asshown by Fig. 3 have projecting strips hlw extending their lengthcrosswise to overhang the spaces between the laths beneath.

The strips l lw which intervene between the base members 15 which carrythe blades l6 as shown by Fig. 3, by pressing upon the leaves or fiberst extending from said leaves to will force those down between the bladesit in order that said blades may pierce the fibers t, or the fiberswhich have been extracted from said leaf while the said leaf is beingstill carried forward in the direction indicated by the arrows 1; shownin the several drawings.

The lattices M, Ma, i412 and Me are carried around their sprocket wheelsH and 12 in order to be moved in the directions shown by the arrows 15Thus it will be observed that the lattices described move in paths whichare at right angles to the paths in which the feeding belts 2, 2a and2b, 20 travel. Therefore as the belts 2, 2a, 2b and 2c are the feedingbelts which receive the leaves w as they are fed thereto, these leavesare carried laterally towards the ends or edges of the lattices referredto. By these means and since the leaves are fed at the feeding end of.

the chains 2, 2a, 2b and 20 (as shown by Fig. 4) they travel with theleading edges along the paths of the chains described so that theyencounter the projections l6 which are moving crosswise their path.Consequently these projections are caused to pierce the said leaves toand after piercing said leaves they move longitudinally along said leafuntil all the loose matter thereon and all the loose matter adhering, tothe fibers from said leaves is carried away by the scraping actions ofsaid members l6, and this engaging, removing and scraping (as well asthe separating actions that the blades 16 have upon the bundles offibers t as these are passing over same) eifects the complete separationof each fiber from its neighbour so that when. finished at the end oftheir operations by the actions of the lattices l4 and Ma the fibersfrom the leading end of the leaves are perfectly cleared and cleaned,while those from the rear edges are also cleaned and cleared in order tobe deposited at the end of the path of motion of the chains 21) and 2cof the stationary table or support from which they may be removed forpacking, bundling or like treatment as may be desired.

In order to secure the desired scraping effect of the blades It upon thefibers t as they are traveling through the machine, said blades are madewith a curved front edge, a rounded top and a straight back edge asclearly shown in side views in Figures 5, 7 and 8, and in their simplestform are perfectly straight and even. As previously stated the actualfront edge corresponding to the thickness of the metal is square to thesides of the blade. The scraping effect may be increased if the top ofthe blade is offset as shown in Figure 10, while the upper end may alsobe twisted to facilitate entry between the fibers. In this case thelower part of the blade is maintained square so that the angularity ofthese edges is an acute angle to the fibers t that are pulled againstthe rear edges 1610 of the blades i8 and said fibers will therefore begreatly stressed and made to spread so that on being next laid hold ofby the succeeding blades the separate fibers will be engaged with on theopposite side of the next blade because of the separation and spreadingactions referred to. Consequently such spreading actions are ofimportance in the quick working of the machine to perform the functionsof scraping and cleaning as desired.

I may also have the blades it formed with offset tips as shown at [6:17(Fig. 10) in which case as the fibers come in contact with the inclinedcenter parts they are strained downwardly and continue to move laterallyduring all the motions of the blades as carried by their respectivelattices Ma and Me. In this manner the dividing and splitting up 01' thebundles of fibers is effected so that ultimately each fiber is separatedfrom its neighbour and all the fibers are delivered in their separatepositions and free of each other, as well as being free of any gummymatter which in nature is associated with them.

It may be found advantageous to have certain of the upper ends i631 ofthe blades l6 twisted or turned from being in strict alignment with thepath of motion of said blades as is shown by a blade at the end of theseries shown by Fig. 11, since by being in that position they morereadily will enter between the series of threads when such threads areat an angle to the line of travel of the blades I6 as carried by theirrespective lattices.

These blades I6 are held in their base members l5 by the bases of saidblades I6 fitting the longitudinal opening through their respective baseholding members 15, and these may be of varied shapes as shown by Figs.5, 7 and 8, where they are respectively rectangular in cross section,circular in cross section and semi-circular in cross section.

The fixings at I510 are made to suit the outer contour of the openingsmade through them and of the'bases of the blades 16 so that said baseholding members l5 will be of the shapes or contour shown by Figs. 5, '7and 8.

When the base members l are of cylindrical contour or semi-cylindricalcontour. as shown by Figs. 7 and 8 the retaining or holding membersi511) have an inwardly extending projection 31 shown by Fig. 9 so thatsaid projection will fit in a slot extending lengthwise the cylindricalor semi-cylindrical retaining members l5 as shown by Figs. 7 and 8. Thusthese latter are more firmly secured and held against rotation.

In order to secure the spaces between the blades 16 I have spacingpieces 3! of the proper contour that are placed within the retainingmembers l5 and I510 so that according to the number of said spacingpieces so will the distance or space apart be secured for the blades I6.

The spacing members, as well as the blades l6, are held together eitherby a rectangular bolt or bar I55- (shown by Fig. 5) extending throughsame and having its outer ends screw-threaded and nuts mounted thereon,or the cylindrical rods I5t may be used as is shown by Figs. 7 and 8, inwhich latter case the said rod has screwed nuts I 5p mounted thereon tobind the whole together throughout the length of the member 15 withinwhich they are mounted.

I may arrange said blades IE to be spaced so that one section, as thecommencing section shown on the left of the diagram (Fig. 12), may bethe coarsest pitch, while the next may be of less pitch, and thesucceeding ones again of lesser pitch in order that the threads passingthrough and between them to be cleaned and scraped by them will finallypass through the closer spaced blades at the right hand of Fig. 12, inwhich the scraping actions as described in reference to the stressingand angular strain put upon them and shown by Fig. 11 will be the finalfinishing of the threads before same are discharged from the machine.

In the treatment of the leaves as above described a tube or conduit 4a:is made use of for conveying water (which may be hot or cold) throughsaid tube 4:1: and along same to be supplied in jets through theorifices 43 leading from said jets, and which orifices may be covered bya plate 41 as is shown by Fig. 3 so that they may be shut-off or openedas occasion may require. It may be advantageous to have the conduit 4min sections as it extends lengthwise the machines in order that thewater or liquid supplied thereby may be varied for difierent sections inorder that the last section when desired may supply a liquid containingsoapy or other ingredients to treat the fibers as they are passingbetween the finishing blades [6 shown at the extreme end of Fig. 12 ofthe drawings.

Figs. 13 and 14 diagrammatically show the passage of the leaves throughthe machine. Firstly they are fed to the feeding belts at, r. Thesecarry them forward to encounter the lattice belts Mb which comb out thewoody pulp and other matters from the fibers and continue so to do untilthese fibers leave the lattices 14b and are carried by the belts ac tothe lattices M in order that after the former treatment of the fibers bythe lattices Mb to clear the fibers in the extending ends of the leaves,the other lattices I4 clear the fibers from the root ends of the leaves,thus depositing the finally finished fibers t cleaned throughout theirwhole lengths;

Such being the nature and object of my said invention, what I claim is:

l. apparatus for treating fibers derived from the leaves of sisal andlike plants, feeding belts for carrying prepared leaves, two sets oftravelling lattices mounted to travel laterally in two directionstherefrom, tubular holders mounted on said lattices and extendingtransversely thereon, each said holder having a longitudinal slottherein, a series of blades supported by each said holder, each saidblade having a base portion within the holder, spacing elements withinthe holders between successive blades, and a longitudinal securingmember extending through each series of blades and the spacersassociated therewith.

2. In apparatus for treating fibers derived from the leaves of sisal andlike plants, a set of travelling lattices, feeding belts adjacent tosaid lattices for carrying prepared leaves past said lattices, andseries of blades on said lattices, some of said blades being twisted sothat their free ends make acute angles with the direction of motionthereof.

3. In apparatus for treating fibers derived from the leaves of sisal andlike plants, a set of travelling lattices, feeding belts adjacent tosaid lattices for carrying prepared leaves past said lattices, series ofblades extending across said lattices, and spacers between, successiveblades in each said series, said spacers being progressively narrowerfrom one side of the lattices to the other, some of said blades beingtwisted so that their free ends make acute angles with the direction ofmotion of the blades.

JAMES MCCRAE.

